Korean Panax ginseng has long been regarded as a valuable panacea in the treatment of some physical disorders due to its various therapeutic effects. When Panax ginseng is intended for use in the treatment of various diseases, however, its shortcomings are that a) saponin, a therapeutic ingredient, is metabolized by intestinal bacteria, and b) since the intestinal bacteria groups are susceptible to person's physical constitution and his lifestyle of foods, there is a possibility that an individual differences in a saponin metabolism may occur, thus affecting the therapeutic effects in the long run. To comply with this matter, the inventors have extensively studied the therapeutic effects on the metabolites of Panax saponins in the body, and have come to know that the saponins metabolized by intestinal bacteria are entities absorbed from the intestinal tract, thus exhibiting immunopotentiating actions including inhibitory actions on the vascularization of tumors and extravasation of cancer cells. With this in mind, the inventors have paved the way for developing Panax saponins as absorbed entities of the saponins to be used as a novel type of anticancer agent, which is not affected by the differences of each intestinal bacteria group (ref: Korean Patent Application No. 4217 filed on 1996).
The process for the preparation of the above mentioned metabolites of Panax ginseng saponins, i.e., 20-O-.beta.-D-glucopyranosyl-20(s)-protopanaxadiol, named compound K and 20-O-.alpha.-L-arabinoopyranosyl(1.fwdarw.6)-.beta.-D-glucopyranosyl!-20(s )-protopanax adiol, named compound Y, has been already reported by utilizing some enzymes produced by the intestinal bacteria derived from Aspergillus niger, soil strain, rat's and the human's faeces ref: Yoshioka, I.: Chem. Pharm. Bull., 20, 2418(1972), Kamida et al.; Pharmacology Journal, 95, 246(1975). Takino et al.: Medicinal ginseng 1989(Public Publications Co., Ltd.), 267(1989), Kaneoka et al.; Japanese Herbal Medicine Journal, 11. 241(1994)!. Further, another method of manufacturing 20-O-.alpha.-L-arabinopuranosyl(1.fwdarw.6)-.beta.-D-glucopyranosyl!-20(s )-protopanaxadiol, named ginsenoside Mc, using intestinal bacteria derived from the human's faeces, has been also reported by the inventor(ref: Korean Patent No. 4217 filed on 1996).
The production of a compound K by the method of using soil strains requires more than 2-week cultivation. Further, in an enzymatic treatment method using crude Hesperidinase produced by Aspergillus niger, one of .beta.-glucosidase, the compound K is produced since the intestinal bacteria in the metabolic route of ginseng saponin produce different enzymes but a compound Y and ginsenoside Mc are not nearly produced due to the production of ginsenoside F2.
Moreover, the method treated by the intestinal bacteria derived from the human's faeces has extended the production of their metabolites ranging from a compound Y and ginsenoside Mc to the compound K whereby their selectivity is low. As such, the conventional manufacturing method has recognized some disadvantages in that a) its production efficiency is low, and b) the selective production activity is low due to additional formation of the cleavable enzyme of sugar in addition to .beta.-glucosidase. Under such circumstances, the prior arts are deemed not to be adequate in efficiently preparing the metabolite of this invention, compound K, compound Y and ginsenoside Mc.